A transmissão não pode se conectar ao rastreador

Question

Eu instalei o software trasmission, mas não consigo configurá-lo. As seguintes linhas, são copiadas do arquivo /var/log/daemon.log :

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Dec 22 10:52:46 raspberrypi transmission-daemon[1904]: Using settings from "/var/lib/transmission-daemon/info" (daemon.c:488)
Dec 22 10:52:46 raspberrypi transmission-daemon[1904]: Saved "/etc/transmission-daemon/settings.json" (bencode.c:1731)
Dec 22 10:52:46 raspberrypi transmission-daemon[1904]: Loaded 1 torrents (session.c:1937)
Dec 22 10:53:01 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Could not connect to tracker (announcer.c:994)
Dec 22 10:53:01 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Retrying announce in 301 seconds. (announcer.c:1003)
Dec 22 10:53:01 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Could not connect to tracker (announcer.c:994)
Dec 22 10:53:01 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Retrying announce in 324 seconds. (announcer.c:1003)
Dec 22 10:53:01 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Could not connect to tracker (announcer.c:994)
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Dec 22 12:34:29 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Starting IPv4 DHT announce (firewalled, 168 nodes) (tr-dht.c:574)
Dec 22 12:36:18 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Connection failed (announcer.c:994)
Dec 22 12:36:18 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Retrying announce in 300 seconds. (announcer.c:1003)
Dec 22 12:37:06 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip IPv4 DHT announce done (tr-dht.c:542)
Dec 22 12:42:24 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Connection failed (announcer.c:994)
Dec 22 12:42:24 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Retrying announce in 910 seconds. (announcer.c:1003)
Dec 22 12:51:54 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Scrape error: Connection failed (announcer.c:1259)
Dec 22 12:51:54 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Retrying scrape in 1859 seconds. (announcer.c:1268)
Dec 22 12:58:38 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Connection failed (announcer.c:994)
Dec 22 12:58:38 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Retrying announce in 3630 seconds. (announcer.c:1003)
Dec 22 13:00:06 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip Starting IPv4 DHT announce (firewalled, 168 nodes) (tr-dht.c:574)
Dec 22 13:02:58 raspberrypi transmission-daemon[1904]: FILE_TO_DOWNLOAD.zip IPv4 DHT announce done (tr-dht.c:542)

Eu tentei baixar o arquivo com o uTorrent, no windows 8, usando o mesmo arquivo torrent, e ele funciona.

Parece que o daemon transmission não pode se conectar aos rastreadores. O que estou perdendo?